The present invention relates to a method and apparatus for generating hot stamped single and multicolor images whereby a transfer is generated at a first station which is part of the apparatus, and a substrate or container is decorated at a second station which also is part of the apparatus. In particular, a transferable image is generated via a hot stamping mechanism (a single or multi-head station) onto a transfer film, and the transfer image is then transferred via hot stamping onto the substrate or container to be decorated at the second station by employing a transfer technique called foilprint.
Hot stamping or transfer decorating is a method of dry printing or dry decorating. An image or design is transferred from a foil or carrier film onto a surface by application of heat and pressure.
The transfer image or design can either be preprinted on a release coated carrier or generated with an engraved, etched or formed die. In the actual stamping or transfer process, a hot die is pressed against the hot stamping foil or transfer film which is sandwiched between the die and the surface to be decorated.
Conventional hot stamping requires a die, as described above, and a hot stamping foil to create an image. The hot stamping foil is a composite of layers of coatings on a carrier, such as polyester film. The coatings are then transferred to a surface as an image, copy or solid. The foils can be metallized or non-metallized (pigments) by design, and can possess a number of inherent qualities.
Preprinted images are formed by printing a copy, text or design via silk-screen, gravure, flexo or offset onto a release coated carrier such as paper or polyester film also called a transfer film. The completed transfer, which also includes an adhesive layer, is then off-line transferred via hot stamping onto a surface to be decorated.
U.S. Pat. No. 4,409,063 (Brown) discloses an apparatus and process for hot-stamping molded plastic containers in which the container is moved passed a heated die having a platen with a printing die, the die being universally movable so that linear uniform pressure is exerted between a confronting container surface and the die surface. The uniform linear pressure between the container and the die, transfers foil to the accompaniment of rotation of the container so that a lamination of the foil is transferred onto the container surface.
Another known method is pad printing wherein wet ink is transferred from an engraved plate to a substrate. A solvent or water based ink system is wiped onto an engraved metal plate and the subsequent design or image is then picked up by a soft rubber ink pad, and transferred onto the substrate or part to be decorated. Both operations are accomplished on an apparatus referred to as a pad printer.
As is the case with any wet printing system, the pad transfer image must undergo a drying operation. Multi-colored designs are accomplished by moving the substrate or part to be decorated from one pad printing station to another. Accordingly, such wet printing processes are disadvantageous in that they often require pre-printing treatment including drying time and wet handling in addition to wet cleanup of rollers, ink wells, etc. Further, any wet residue must be formally disposed of in accordance with the Environmental Protection Agency (EPA) regulations.